Home |
Search |
Today's Posts |
#71
![]() |
|||
|
|||
![]()
On Thu, 03 Nov 2005 13:44:47 -0800, Jim Kelley
wrote: If you wouldn't mind, try moving your Yagi a half wave forward or reverse. Moving back one half wave: EZNEC+ ver. 4.0 Vert Yagi in Ring of Sources 11/3/2005 2:37:02 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 1.655 V. at -135.94 deg. Current = 0.1379 A. at -135.94 deg. Impedance = 12 + J 0 ohms Power = 0.2283 watts Total applied power = 2000 watts Total load power = 0.2283 watts Total load loss = 0.0 dB moving it such that its "driven" element is dead center to all radiators (original configuration had the reflector in dead center): EZNEC+ ver. 4.0 Vert Yagi in Ring of Sources 11/3/2005 2:40:58 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 1.584 V. at -22.13 deg. Current = 0.132 A. at -22.13 deg. Impedance = 12 + J 0 ohms Power = 0.2091 watts Total applied power = 2000 watts Total load power = 0.2091 watts Total load loss = 0.0 dB 73's Richard Clark, KB7QHC |
#72
![]() |
|||
|
|||
![]() Richard Clark wrote: On Thu, 03 Nov 2005 13:44:47 -0800, Jim Kelley wrote: If you wouldn't mind, try moving your Yagi a half wave forward or reverse. Moving back one half wave: EZNEC+ ver. 4.0 Vert Yagi in Ring of Sources 11/3/2005 2:37:02 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 1.655 V. at -135.94 deg. Current = 0.1379 A. at -135.94 deg. Impedance = 12 + J 0 ohms Power = 0.2283 watts Total applied power = 2000 watts Total load power = 0.2283 watts Total load loss = 0.0 dB moving it such that its "driven" element is dead center to all radiators (original configuration had the reflector in dead center): EZNEC+ ver. 4.0 Vert Yagi in Ring of Sources 11/3/2005 2:40:58 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 1.584 V. at -22.13 deg. Current = 0.132 A. at -22.13 deg. Impedance = 12 + J 0 ohms Power = 0.2091 watts Total applied power = 2000 watts Total load power = 0.2091 watts Total load loss = 0.0 dB 73's Richard Clark, KB7QHC It looks like you'd have to use an array of non-coherent sources in order to get rid of the phase cancellation effects (and really see what's going on). Thanks Richard. ac6xg |
#73
![]() |
|||
|
|||
![]()
On Thu, 03 Nov 2005 15:13:53 -0800, Jim Kelley
wrote: It looks like you'd have to use an array of non-coherent sources in order to get rid of the phase cancellation effects (and really see what's going on). Hi Jim, Then it would be answering a different problem. 73's Richard Clark, KB7QHC |
#74
![]() |
|||
|
|||
![]() Richard Clark wrote: On Thu, 03 Nov 2005 15:13:53 -0800, Jim Kelley wrote: It looks like you'd have to use an array of non-coherent sources in order to get rid of the phase cancellation effects (and really see what's going on). Hi Jim, Then it would be answering a different problem. 73's Richard Clark, KB7QHC An antenna one, rather than an antenna +/- source one. Yes. 73, ac6xg |
#75
![]() |
|||
|
|||
![]()
On Thu, 03 Nov 2005 15:13:53 -0800, Jim Kelley
wrote: use an array of non-coherent sources EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:39:03 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.002611 V. at -33.23 deg. Current = 3.627E-05 A. at -33.23 deg. Impedance = 72 + J 0 ohms Power = 9.47E-08 watts Total applied power = 1364 watts Total load power = 9.47E-08 watts Total load loss = 0.0 dB then moved quarterwave: EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:41:17 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.00676 V. at -110.1 deg. Current = 9.389E-05 A. at -110.1 deg. Impedance = 72 + J 0 ohms Power = 6.348E-07 watts Total applied power = 1364 watts Total load power = 6.348E-07 watts Total load loss = 0.0 dB then moved backwards a quarterwave EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:44:52 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.004604 V. at 29.97 deg. Current = 6.395E-05 A. at 29.97 deg. Impedance = 72 + J 0 ohms Power = 2.944E-07 watts Total applied power = 1364 watts Total load power = 2.944E-07 watts Total load loss = 0.0 dB EZNEC+ ver. 4.0 Yagi in Ring of Rnd Sources 11/3/2005 5:48:14 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.07004 V. at 66.62 deg. Current = 0.005837 A. at 66.62 deg. Impedance = 12 + J 0 ohms Power = 0.0004088 watts Total applied power = 1364 watts Total load power = 0.0004088 watts Total load loss = 0.0 dB moved back halfwave: EZNEC+ ver. 4.0 Yagi in Ring of Rnd Sources 11/3/2005 5:51:43 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.09133 V. at -53.63 deg. Current = 0.007611 A. at -53.63 deg. Impedance = 12 + J 0 ohms Power = 0.0006952 watts Total applied power = 1364 watts Total load power = 0.0006952 watts Total load loss = 0.0 dB (and really see what's going on) Hmmm, at least 1000 times more response... so what's going on? (aside from a possibly poor implementation of random). Trying to refine the sources table with tighter random assignments is positively brutal under EZNEC's primitive (read no) handling of columnar data. 73's Richard Clark, KB7QHC |
#76
![]() |
|||
|
|||
![]()
Very nice work. Dissapointingly ambiguous results.
Thank you. ac6xg Richard Clark wrote: On Thu, 03 Nov 2005 15:13:53 -0800, Jim Kelley wrote: use an array of non-coherent sources EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:39:03 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.002611 V. at -33.23 deg. Current = 3.627E-05 A. at -33.23 deg. Impedance = 72 + J 0 ohms Power = 9.47E-08 watts Total applied power = 1364 watts Total load power = 9.47E-08 watts Total load loss = 0.0 dB then moved quarterwave: EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:41:17 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.00676 V. at -110.1 deg. Current = 9.389E-05 A. at -110.1 deg. Impedance = 72 + J 0 ohms Power = 6.348E-07 watts Total applied power = 1364 watts Total load power = 6.348E-07 watts Total load loss = 0.0 dB then moved backwards a quarterwave EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:44:52 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.004604 V. at 29.97 deg. Current = 6.395E-05 A. at 29.97 deg. Impedance = 72 + J 0 ohms Power = 2.944E-07 watts Total applied power = 1364 watts Total load power = 2.944E-07 watts Total load loss = 0.0 dB EZNEC+ ver. 4.0 Yagi in Ring of Rnd Sources 11/3/2005 5:48:14 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.07004 V. at 66.62 deg. Current = 0.005837 A. at 66.62 deg. Impedance = 12 + J 0 ohms Power = 0.0004088 watts Total applied power = 1364 watts Total load power = 0.0004088 watts Total load loss = 0.0 dB moved back halfwave: EZNEC+ ver. 4.0 Yagi in Ring of Rnd Sources 11/3/2005 5:51:43 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.09133 V. at -53.63 deg. Current = 0.007611 A. at -53.63 deg. Impedance = 12 + J 0 ohms Power = 0.0006952 watts Total applied power = 1364 watts Total load power = 0.0006952 watts Total load loss = 0.0 dB (and really see what's going on) Hmmm, at least 1000 times more response... so what's going on? (aside from a possibly poor implementation of random). Trying to refine the sources table with tighter random assignments is positively brutal under EZNEC's primitive (read no) handling of columnar data. 73's Richard Clark, KB7QHC |
#77
![]() |
|||
|
|||
![]()
Richard,
It's not clear what aspect of your sources is "Rnd", but the fact that they are monochromatic is still problematic. 73, ac6xg Jim Kelley wrote: Very nice work. Dissapointingly ambiguous results. Thank you. ac6xg Richard Clark wrote: On Thu, 03 Nov 2005 15:13:53 -0800, Jim Kelley wrote: use an array of non-coherent sources EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:39:03 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.002611 V. at -33.23 deg. Current = 3.627E-05 A. at -33.23 deg. Impedance = 72 + J 0 ohms Power = 9.47E-08 watts Total applied power = 1364 watts Total load power = 9.47E-08 watts Total load loss = 0.0 dB then moved quarterwave: EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:41:17 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.00676 V. at -110.1 deg. Current = 9.389E-05 A. at -110.1 deg. Impedance = 72 + J 0 ohms Power = 6.348E-07 watts Total applied power = 1364 watts Total load power = 6.348E-07 watts Total load loss = 0.0 dB then moved backwards a quarterwave EZNEC+ ver. 4.0 Dipole in Ring of Rnd Sources 11/3/2005 5:44:52 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.004604 V. at 29.97 deg. Current = 6.395E-05 A. at 29.97 deg. Impedance = 72 + J 0 ohms Power = 2.944E-07 watts Total applied power = 1364 watts Total load power = 2.944E-07 watts Total load loss = 0.0 dB EZNEC+ ver. 4.0 Yagi in Ring of Rnd Sources 11/3/2005 5:48:14 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.07004 V. at 66.62 deg. Current = 0.005837 A. at 66.62 deg. Impedance = 12 + J 0 ohms Power = 0.0004088 watts Total applied power = 1364 watts Total load power = 0.0004088 watts Total load loss = 0.0 dB moved back halfwave: EZNEC+ ver. 4.0 Yagi in Ring of Rnd Sources 11/3/2005 5:51:43 PM --------------- LOAD DATA --------------- Frequency = 70 MHz Load 1 Voltage = 0.09133 V. at -53.63 deg. Current = 0.007611 A. at -53.63 deg. Impedance = 12 + J 0 ohms Power = 0.0006952 watts Total applied power = 1364 watts Total load power = 0.0006952 watts Total load loss = 0.0 dB (and really see what's going on) Hmmm, at least 1000 times more response... so what's going on? (aside from a possibly poor implementation of random). Trying to refine the sources table with tighter random assignments is positively brutal under EZNEC's primitive (read no) handling of columnar data. 73's Richard Clark, KB7QHC |
#78
![]() |
|||
|
|||
![]()
On Fri, 04 Nov 2005 10:32:07 -0800, Jim Kelley
wrote: It's not clear what aspect of your sources is "Rnd", but the fact that they are monochromatic is still problematic. Hi Jim, You lost me on that curve. Monochromatic. The sources exhibit an even distribution of varying phase in a random order. That was tedious to accomplish, but achievable - in a group of 360 possible degrees of phase, you eventually cover the field. On the other hand, if you are suggesting that there needs to be an equally random distribution of frequencies then that has its obvious issues of practicability. What is the lowest frequency and what is the highest frequency? That question has all the hallmarks of which infinity is the biggest? Anyway, I would surmise that if I could achieve both random phase and frequency distribution, then the difference between a simple dipole's response and that of a yagi antenna would be trivial. This would be a given seeing that the parasitic elements would be virtually invisible, rendering the "driven" element un-differentiable from the simple dipole. 73's Richard Clark, KB7QHC |
#79
![]() |
|||
|
|||
![]() Richard Clark wrote: Anyway, I would surmise that if I could achieve both random phase and frequency distribution, then the difference between a simple dipole's response and that of a yagi antenna would be trivial. Trivial would be a nice change. This would be a given seeing that the parasitic elements would be virtually invisible, rendering the "driven" element un-differentiable from the simple dipole. i.e. what Roy said. But I think there's still more to it. I tried to give the other Richard a hint about it but it didn't resonate. 73, ac6xg |
#80
![]() |
|||
|
|||
![]()
Jim Kelley wrote:
i.e. what Roy said. But I think there's still more to it. I tried to give the other Richard a hint about it but it didn't resonate. Then obviously your XC didn't equal your XL. -- 73, Cecil http://www.qsl.net/w5dxp |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Handheld GMRS/FRS radio antenna gain question | Antenna | |||
Imax ground plane question | CB | |||
Antenna Advice | Shortwave | |||
LongWire Antenna | Shortwave | |||
Poor quality low + High TV channels? How much dB in Preamp? | Shortwave |